Virtually-concatenated data traffic is routed in a network comprising at least first and second nodes. The first and second nodes may comprise a source-sink node pair, an ingress-egress node pair, or any other pair of network nodes. For a given traffic demand, a plurality of routes for routing the traffic demand through the network are determined. Each of the routes corresponds to a member of a virtually-concatenated group, such that different portions of the traffic demand are assigned to different members of the virtually-concatenated group.